<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
    <script>
        $(function() {
            $("h3").css("color", "red");
            $("#d01").css("color", "green");
            $(".p01,.p02").css("color", "hotpink");
            $("h3.h01").css("color", "blue");
        });
    </script>
    <style>

    </style>
</head>

<body>
    <h1>水电费水电费</h1>
    <h3>水电费水电费是的发生的</h3>
    <div id="d01">是的发生的</div>
    <p class="p01">双方都</p>
    <p class="p02">水电费水电费</p>
    <h3 class="h01">嘿嘿嘿黑</h3>
</body>

</html>